Honeycomb fill for cooling tower



Sept. 13, 1966 B. B. BRAND ETAL HONEYCOMB FILL FOR COOLING TOWER 2 Sheets-Sheet 1 Filed Aug. 22, 1965 7/2 2 5. INVE T0125 EFL/6Q 5. P005 BY Jena/67 .f'off l 9 m T7'ORNE Y5.

Sept. 13, 1966 B. B. BRAND ETAL HONEYCOMB FILL FOR COOLING TOWER 2 Sheets-Sheet 2 Filed Aug. 22, 1965 INVENTORS, Bruce 5. e/e/w/a J.

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United States Patent 3,272,484 HONEYCOMB FILL FOR COOLING TOWER Bruce B. Brand, Prairie Village, Kans., and Jerald J. Scott, Kansas City, Mo., assignors to Havens Structural Steel Co., Kansas City, Mo., a corporation of Missouri Filed Aug. 22, 1963, Ser. No. 303,868 3 Claims. '(Cl. 26124) This invention deals generally with liquid-gas contact heat exchangers, and refers more particularly to the provision of an improved fill structure especially suitable for use in those types of heat exchangers commonly known as cross flow cooling towers.

One of the principal objectives of the invention is to provide an improved fill structure by which the capacity of the tower is materially increased without requiring enlargement of the over-all dimensions of the tower. This objective is achieved mainly in the provision of more area of wettable surface per volumetric unit of the fill structure and in the improved liquid to gas contact achieved in the structure.

Another and related object of the invention is to provide a fill structure for cooling towers in which the gasliquid contact is made substantially uniform at all points in the fill structure.

Still another object of the invention is to provide a fill structure of the character described which is relatively easy to manufacture and to assemble into a cooling tower which is of low cost, which can be handled with ease and facility, and which nevertheless withstands long and rugged use.

Other and further objects of the invention together with the features of novelty appurtenant thereto will appear in the course of the following description.

In the accompanying drawings which form a part of the specification and are to be read in conjunction therewith and in which like reference numerals indicate like parts in the various views;

FIG. 1 is a generally schematic side elevational view of a typical cross flow cooling tower embodying a preferred form of fill structure according to the invention, parts of the tower being broken away for purposes of illustration;

FIG. 2 is a greatly enlarged fragmentary view taken along the line 2-2 of FIG. 1 in the direction of the arrows and showing the upper corner of a fill structure section of the type shown in FIG. 1, parts being shown in section for purposes of illustration;

FIG. 3 is a fragmentary view taken from the right-hand side of FIG. 2;

FIG. 4 is a view of a portion of a fill structure section like that of FIGS. 2 and 3 but with the fill section in the flattened, compacted condition utilized during formation of the internal liquid transmission apertures therein;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 4 in the direction of the arrows;

FIG. 6 is an edge elevational view of a composite element which is assembled in vertically stacked relationship with like elements to form a modified form of fill section according to and embodying the invention;

FIG. 7 is a top plan view of the element of FIG. 6; and

FIG. 8 is a view similar to FIG. 2 showing a fill section made up of the elements like those shown in FIG. 6, parts being shown in section for purposes of illustration.

Referring to the drawings and initially to FIGS. 1-3, inclusive, reference numeral 10 indicates generally a cross flow cooling tower having conventional external and internal construction except for the fill structure. The tower is generally rectangular in configuration and has the fan 11 for drawing air through the interior of the 3,272,484 Patented Sept. 13, 1966 tower in the direction indicated by the arrows. The fan is driven from the motor 12 through the belt connection 13.

Liquid to be cooled is delivered by pipe 14 into a conventional perforated distribution pan or tray 15, from the perforations of which it is discharged by gravity into the fill structure 16 later to be described in detail. A basin 17 receives the cooled water from the fill structure and the water is returned to the system from whence it came (not shown) by the return pipe or drain 18.

The details of construction of the tower are conventional and, therefore, no further description thereof is believed necessary. It will be understood that many changes may be made in the tower structure itself without altering the basic operation of the tower, for example replacing the distribution tray 15 with the conventional pipe headers and spray nozzle laterals which serve to distribute the water uniformly to the top of the fill structure. Likewise, the usual eliminators and screens may be included in the tower.

Turning now to the description of the fill structure itself, in the preferred embodiment this comprises the plurality of substantially identical fill structure sections 19, each of which is of the honeycomb construction illustrated in FIGS. 2 and 3.

The individual sections are of rectangular block-like configuration. They are provided with a width such that they substantially fill the interior of the tower between the opposite side walls. The honeycomb structure has the uniform, substantially hexagonal, parallel passageways 20 and the fill section is so oriented that the passageways 20 are generally aligned with the direction of air flow through the tower.

In the preferred construction, the fill section is manufactured of sheets S of paper impregnated with a suitable corrosion resistant plastic. The paper may be Kraft paper and the honeycomb is formed by joining a plurality of sheets arranged in stacked arrangement. by means of spaced and staggered glue or adhesive strips as at 21, the sheets subsequently being opened away from one another so as to form the honeycomb cells or passageways 20. The plastic impregnate is of a type that once the honeycomb has been opened or expanded, .it can be cured or set so as to hold the structure in the expanded condition.

As earlier noted, the sections 19 are so oriented in the casing that the passageways 20 are aligned substantially with the direction of air flow through the tower. The sections can be upright so that the passageways are truly horizontal, or as illustrated in FIG. 1, they may be tilted slightly from the vertical in order to compensate for the tendency of the water to be moved laterally toward the fan by the air draft as the water progresses downwardly through the fill.

In order to provide for the downward passage of liquid in directions transverse to the axes of the honeycomb cells, each horizontal row of honeycomb cells is apertured at spaced locations along the length thereof so as to communicate with the adjacent row of cells therebelow. The aperturing of the cells is preferably done in the preferred embodiment here being described by drilling or punching out material on a line straight across the fill section from one side to the other, as best seen in FIG. 3. The apertures which provide communication with the top row of cells are indicated at 22. Those providing communication between the top row of cells and the row next below are shown at 23, and each subsequent row is identified by the next numeral, i.e. 24, 25, 26 and 27. While only the upper corner fragment of the complete fill section is shown in FIGS. 2 and 3, it will be understood that the same pattern progresses from top to bottom of the fill structure so that liquid can progress interiorly of the fill section from the top completely down through the fill section and out at the bottom. The succeeding rows of apertures are staggered so that the liquid will be caused to distribute itself on the cell walls during its passage therethrough in the form of films.

The manufacture of the sections 19, particularly with respect to the provision of the transverse cell interconnecting apertures or openings 2227, is something which can easily be accomplished. Referring to FIGS. 4 and 5, this shows a corner fragment of the honeycomb structure prior to expansion, that is with the sheets S of the structure in flattened, parallel condition. It will be understood that when the sheets are in this condition the glue lines for interconnecting the sheets have already been applied so that When the sheets are pulled apart the honeycomb will be formed. The openings can now be formed by punching or drilling out sections of material as illustrated, the line of punching or drilling being so located that they come quite close to, or bite slightly into the glued areas. In this fashion, the openings are sure to be so located that liquid flows into a cell centrally at the top and departs therefrom essentially at the bottom. Thereafter, when the sheets are expanded to complete the honeycomb, the apertures Will be located as illustrated in FIGS. 2 and 3.

Because of the transverse alignment of the apertures or openings in horizontal rows, they also provide a means of hanging or suspending the fill sections 19 in the tower. If desired, rods or ropes can be run through one or more sets of openings and anchored or otherwise secured at the opposite ends to the tower wall or framework. Because of scale, these rods are not shown in FIG. 1, but it will be understood that they pass transversely through the fill section and connect with the side walls or tower framework. In order to hold the inclined position, at least two rods for each section will be employed. Preferably, the rods should be of smaller diameter than the diameter of the openings whereby to permit the liquid to flow around the rods, although this is not imperative since the blockage is minimal anyhow.

The fill structure of our invention has many advantages over conventional fills. It is light in weight, thus reducing considerably the over-all weight of the tower in comparison with conventional ones. There is more square feet of wettable surface area per cubic foot of fill, and thus more water can be cooled per cubic foot of fill. The water is formed into thin films moving from cell to cell downwardly through the cells of the honeycomb and thus there is also much better and more intimate water-to-air contact than in slat or deck type towers. The air is uniformly distributed by virtue of the honeycomb construction, and the fill structure assures that optimum air-towater contact will take place.

FIGS. 6, 7 and 8 all relate to a modified form of fill section which embodies the invention and can be used in much the same fashion as described in connection with the preceding embodiment.

In the modified form, the fill section is made up of vertically stacked plies P of the nature shown in FIGS. 6 and 7. Each ply comprises the flat base sheet S and corrugated top element. The manner of construction of the plies and their composition is disclosed fully in Patent No. 2,986,379 and reference may be had thereto for further explanation. It is enough to note for the purposes of this application that, generally speaking, the ply material is asbestos impregnated with a phenolic resin.

The plies are stacked vertically in the manner shown in FIG. 8 and it will be evident that the corrugated elements cooperate with the sheets S to form parallel passageways 120 much like the passageways 20 of the preceding embodiment. The modified form of fill section is placed in the tower in much the same manner as in the preceding embodiment, that is with the passageways aligned generally with the direction of movement of the air.

To provide a means of passage for the water downwardly through the tower, each of the plies P is provided with horizontally spaced perforations located at the valleys of the corrugations, the perforations being identified by reference numeral 122. Each valley has a series of perforations longitudinally spaced therealong. The perforations extend into and through the sheet S as indicated at 123. It will be noted that the perforations are of sufiicient size that communication is established into the interior of the corrugations between the valleys.

The plies are so stacked that the valleys of the uppermost ply register with the peaks or ridges of the corrugations on the next ply therebelow. Because of this arrangement, water descending through the stack will flow down the slope of the corrugations toward the perforations, will flow through the perforations and will be divided again to flow down the diverging slopes of the corrugation therebelow. This process is repeated all the way through the stack and consequently it will be evident that water is finally divided into films which extend completely through the fill section. As in the preceding embodiment, this establishes excellent air-to-water contact and provides a substantially improved capacity for the tower when compared with conventional fills.

In the modified form of the invention, the apertures are not located so as to provide means for supporting the fill sections from the rods described in the preceding embodiment. However, the very nature of the fill makes it easy to support, at its bottom, on the conventional expanded metal basket or support.

From the foregoing, it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure. While we have described certain specific materials of which the honeycomb is made, We do not desired to be limited thereto since other materials can be used in constructing the honeycomb.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is Within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompany drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described our invention, we claim:

1. In a cross flow cooling tower, the combination of a hollow, main tower body, a source of liquid at the top of said body, means for drawing air in a substantially horizontal path through said body, and a fill structure within said body, said fill structure comprising a plurality of abutted corrugated sheets located below said source of liquid, said corrugations forming substantially horizontal, open-ended, parallel passageways arranged with their axes in the direction of air flow, said passageways having lateral openings therein at intervals throughout the fill structure and providing communication between vertically adjacent passageways whereby to provide for dispersed gravity fiow of liquid.

2. In a cross flow cooling tower, the combination of a hollow, main tower body, a source of liquid of the top of said body, means for drawing air in a substantially horizontal path through said body, and a fill structure within said body, said fill structure comprising a honeycomb member including a plurality of abutted corrugated elements located below said source of liquid, said corrugations forming substantially horizontal, open-ended, parallel cells arranged with their axes in the direction of the air fiow, the cell walls having transverse, horizontally aligned apertures therethrough at intervals throughout the honeycomb and providing communication between vertically adjacent cells whereby to provide for dispersed ravity flow of liquid.

3. In a cross fiow cooling tower, the combination of a hollow main tower body, a source of liquid at the top of said body, means for drawing air in a substantially horizontal path through said body, and a fill structure within said body, said fill structure comprising a honeycomb member located below said source of liquid, including a plurality of parallel, separated, fiat sheets, and corrugated elements sandwiched between the fiat sheets and defining with the flat sheets substantially horizontal open-ended parallel cells arranged with their axes in the direction of the air fiow, said cells apertured at intervals along the conjunction between the corrugations and flat sheets and throughout the honeycomb structure, whereby to provide for dispersed gravity flow of liquid.

References Cited by the Examiner UNITED STATES PATENTS 2,206,440 7/1940 Walker 261-112 2,490,079 12/ 1949 Melvill.

3,013,781 12/1961 Haselden 261-112 3,044,237 7/1962 Mart.

3,065,587 11/1962 Fordyce et al.

3,084,918 4/1963 Kohl et al. 261-112 10 HARRY B. THORNTON, Primary Examiner.

T. R. MILES, Assistanl Examiner. 

1. IN A CROSS FLOW COOLING TOWER, THE COMBINATION OF A HOLLOW, MAIN TOWER BODY, A SOURCE OF LIQUID AT THE TOP OF SAID BODY, MEANS FOR DRAWING AIR IN A SUBSTANTIALLY HORIZONTAL PATH THROUGH SAID BODY, AND A FILL STRUCTURE WITHIN SAID BODY, SAID FILL STRUCTURE COMPRISING A PLURALITY OF ABUTTED CORRUGATED SHEETS LOCATED BELOW SAID SOURCE OF LIQUID, SAID CORRUGATIONS FORMING SUBSTANTIALLY HORIZONTAL, OPEN-ENDED, PARALLEL PASSAGEWAYS ARRANGED WITH THEIR AXES IN THE DIRECTION OF AIR FLOW, SAID PASSAGEWAYS HAVING LATERAL OPENINGS THEREIN AT INTERVALS THROUGHOUT THE FILL STRUCTURE AND PROVIDING COMMUNICATION BETWEEN VERTICALLY ADJACENT PASSAGEWAYS WHEREBY TO PROVIDE FOR DISPERSED GRAVITY FLOW OF LIQUID
 3. IN A CROSS COOLING TOWER, THE COMBINATION OF A HOLLOW MAIN TOWER BODY, A SOURCE OF LIQUID AT THE TOP OF SAID BODY, MEANS FOR DRAWING AIR IN A SUBSTANTIALLY HORIZONTAL PATH THROUGH SAID BODY, AND A FILL STRUCTURE WITHIN SAID BODY, SAID FILL STRUCTURE COMPRISING A HONEYCOMB MEMBER LOCATED BELOW SAID SOURCE OF LIQUID, INCLUDING A PLURALITY OF PARALLEL, SEPARATED, FLAT SHEETS, AND CORRUGATED ELEMENTS SANDWICHED BETWEEN THE FLAT SHEETS AND DEFINING WITH THE FLAT SHEETS SUBSTANTIALLY HORIZONTAL OPEN-ENDED PARALLEL CELLS ARRANGED WITH THEIR AXES IN THE DIRECTION OF THE AIR FLOW, SAID CELLS APERTURED AT INTERVALS ALONG THE CONJUNCTION BETWEEN THE CORRUGATIONS AND FLAT SHEETS AND THROUGHOUT THE HONEYCOMB STRUCTURE, WHEREBY TO PROVIDE FOR DISPERSED GRAVITY FLOW OF LIQUID. 